Counterargument: "=" is YAMLization. It prioritizes concision and an abstracted ideal of "readability"[1] at the expense of mental model and ease of use. Every non-obvious feature like this has cost. Every user who sees this for the first time is going to be confused. Every time a language or syntax adds a "shorthand" feature like this it makes itself less accessible.

And in this case I think the value is really pretty low. That particular "=" syntax is really mostly just useful for dumping runtime state at debug time. And the world is filled with tools that can do that for you with even more concision.

[1] Which doesn't really correspond to general comprehension. It means something more like "readability for experts".